Republicans, many from tobacco states, put up some resistance – forcing the Senate into a second week of debate on the bill and three procedural votes to ensure its final passage.

But the bill passed 79 to 17, with one Democrat joining 16 Republicans in opposition. The Senate now needs to reconcile its bill with the House’s version, which passed 298 to 112 on April 2. President Obama says he will sign the compromise bill into law.

Lawmakers say that one of the first things many new members learned when they came to Washington was to avoid crossing tobacco companies.

Tobacco lobbyists have contributed more than $62.1 million to congressional campaigns since 1990, 74 percent to Republicans, according to the Center for Responsive Politics in Washington.

“Congress moves slowly, the tobacco industry is powerful, and individual senators have tremendous power to slow and delay and prevent things from happening,” says Paul Billings, vice president of national policy and advocacy for the National Lung Association in Washington.

The shift began in 1987, 23 years after the Surgeon General released a study linking smoking to severe health problems. In that year, Congress banned smoking on airline flights within the US that lasted two hours or less.

“So many members of the House flew in airplanes and couldn’t stand the fiction of ‘smoking areas,’” said Sen. Richard Durbin (D) of Illinois, a longtime leader in antismoking legislation.

The July 13 House vote was 198 to 193.

“That was the first domino to fall,” Representative Durbin added. “People started to say secondary smoke is dangerous on airplanes – it could be dangerous in other places.”

Evidence was building. In 1982, Surgeon General C. Everett Koop had called smoking “the chief single, avoidable cause of death in our society and the most important public health issue of our time.”

Cigarette smoking now accounts for 1 in 5 deaths every year in the US – more than HIV AIDS, alcohol use, illegal drug use, traffic accidents, suicides, and murders combined, according to the Centers for Disease Control and Prevention (CDC).

Yet even in recent times, the industry had appeared unrepentant. Seven tobacco executives, testifying before a House panel in 1994, famously declared under oath that nicotine was not addictive.

In 2004, industry giant Altria Group, Inc., formerly Philip Morris, split with the other tobacco companies and endorsed FDA regulation of the tobacco industry. But industry leaders rallied to oppose a 2006 Department of Justice lawsuit charging tobacco companies with racketeering for making false claims about the dangers of smoking, including denying that it is marketed to children.

This May 22, the US court of appeals affirmed a lower court ruling finding the companies guilty.

Commenting on the decades it took Congress to act, Sen. Frank Lautenberg (D) of New Jersey, who drafted the Senate version of the 1987 airline smoking ban, said: “The Senate has the speed of a centipede. Sometimes it takes a long time for all parts of the body to get moving, but we’re here." [Editor's note: The original version misidentified the senator's home state.]